Five Weeks in a Balloon
Former Experiments.--The Doctor's Five Receptacles.--The Gas Cylinder.-- The
Calorifere.--The System of Manoeuvring.--Success certain.
"The attempt has often been made, gentlemen," said the doctor, "to rise and descend at
will, without losing ballast or gas from the balloon. A French aeronaut, M. Meunier, tried
to accomplish this by compressing air in an inner receptacle. A Belgian, Dr. Van Hecke,
by means of wings and paddles, obtained a vertical power that would have sufficed in
most cases, but the practical results secured from these experiments have been
"I therefore resolved to go about the thing more directly; so, at the start, I dispensed with
ballast altogether, excepting as a provision for cases of special emergency, such as the
breakage of my apparatus, or the necessity of ascending very suddenly, so as to avoid
"My means of ascent and descent consist simply in dilating or contracting the gas that is
in the balloon by the application of different temperatures, and here is the method of
obtaining that result.
"You saw me bring on board with the car several cases or receptacles, the use of which
you may not have understood. They are five in number.
"The first contains about twenty-five gallons of water, to which I add a few drops of
sulphuric acid, so as to augment its capacity as a conductor of electricity, and then I
decompose it by means of a powerful Buntzen battery. Water, as you know, consists of
two parts of hydrogen to one of oxygen gas.
"The latter, through the action of the battery, passes at its positive pole into the second
receptacle. A third receptacle, placed above the second one, and of double its capacity,
receives the hydrogen passing into it by the negative pole.
"Stopcocks, of which one has an orifice twice the size of the other, communicate between
these receptacles and a fourth one, which is called the mixture reservoir, since in it the
two gases obtained by the decomposition of the water do really commingle. The capacity
of this fourth tank is about forty-one cubic feet.
"On the upper part of this tank is a platinum tube provided with a stopcock.
"You will now readily understand, gentlemen, the apparatus that I have described to you
is really a gas cylinder and blow-pipe for oxygen and hydrogen, the heat of which
exceeds that of a forge fire.